(6R,7R)-7-[[(2Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-[(triphenylmethoxy)imino]acetyl]amino]-3-[(E)-[(3'R)-1'-[(1,1-dimethylethoxy)carbonyl]-2-oxo-[1,3'-bipyrrolidin]-3-ylidene]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid diphenylmethyl ester

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 August 2017 to 13 September 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

OECD GUIDELINES FOR TESTING OF CHEMICALS (423, adopted at 17th Dec. 2001)

Deviations:

yes

Remarks:

Due to technical reason, relative humidity values (maximum of 80 %) outside the expected range of 30-70 % were recorded during the acclimation period. This deviation has no presumed impact on the outcome or integrity of the study.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Version / remarks:

Commission Regulation (EC) No 440/2008 of 30 May 2008, B.1.tris

Deviations:

yes

Remarks:

Due to technical reason, relative humidity values (maximum of 80 %) outside the expected range of 30-70 % were recorded during the acclimation period. This deviation has no presumed impact on the outcome or integrity of the study.

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

EPA Health Effects Test Guidelines (OPPTS 870.1100), United States, EPA 712-C-98-190 (1998)

Deviations:

yes

Remarks:

Due to technical reason, relative humidity values (maximum of 80 %) outside the expected range of 30-70 % were recorded during the acclimation period. This deviation has no presumed impact on the outcome or integrity of the study.

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

tert-butyl (3E,3'R)-3-{[(6R,7R)-7-[(2Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-[(triphenylmethoxy)imino]acetamido]-2-[(diphenylmethoxy)carbonyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-yl]methylidene}-2-oxo-[1,3'-bipyrrolidine]-1'-carboxylate

EC Number:

609-463-9

Cas Number:

376653-41-7

Molecular formula:

C57H54N8O8S2

IUPAC Name:

tert-butyl (3E,3'R)-3-{[(6R,7R)-7-[(2Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-[(triphenylmethoxy)imino]acetamido]-2-[(diphenylmethoxy)carbonyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-yl]methylidene}-2-oxo-[1,3'-bipyrrolidine]-1'-carboxylate

Test material form:

solid: particulate/powder

Details on test material:

Name: BAL0001026
CAS number: 376653-41-7
Batch/Lot number: 012
Appearance: Off-white powder
Purity: Content by mass balance: 84.9% w/w
Expiry date: 30 June 2020
Storage conditions: Under inert gas, protected from light and humidity (tight closed container), frozen (≤-15 °C)
Safety precautions: Enhanced safety precautions were applied considering the supplied safety datasheet to assure personnel health and safety.

Specific details on test material used for the study:

No further details specified in the study report.

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Species and strain: CRL:(WI) Wistar rats
Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, D-97633 Sulzfeld
Hygienic level at arrival: SPF
Hygienic level during the study: Standard housing conditions
Number of animals: 6 animals
Sex: Female, nulliparous and non-pregnant
Age of animals at dosing: Young healthy adult rats, 9 weeks old
Body weight at treatment: 220 – 238 g
Acclimatization period: at least 12 days

Husbandry
Animal health: Only healthy animals were used for the test. The staff Veterinarian certified health status.
Number of animal room: 522/1
Housing: 3 animals / cage
Cage type: Type II polypropylene/polycarbonate
Bedding/Nesting: “Lignocel 3/4-S Hygienic Animal Bedding” and “Arbocel crinklets natural” nest building material produced by J. Rettenmaier & Söhne GmbH & Co.KG (D-73494 Rosenberg, Germany) were available to animals during the study.
Lighting period: 12 hours daily, from 6.00 am to 6.00 pm
Temperature: 22 ± 3 °C
Relative humidity: 33-80%
Ventilation: 15 – 20 air exchanges/hour
Enrichment: Animals were housed by group to allow social interaction and with deep wood sawdust bedding to allow digging and other normal rodent activities.
The room temperature and relative humidity were recorded twice daily during the study.

Food and Water Supply
Animals received ssniff® SM R/M "Autoclavable complete diet for rats and mice – breeding and maintenance" produced by ssniff Spezialdiäten GmbH, D-59494 Soest, Germany (Batch no.: 262 21592, expiry date: 31 January 2018), ad libitum, and tap water from the municipal supply, as for human consumption from 500 ml bottles, ad libitum. The food is considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
Water quality control analysis is performed once every three months and microbiological assessment is performed monthly, by Veszprém County Institute of State Public Health and Medical Officer Service (ÁNTSZ, H-8201 Veszprém, József A.u.36., Hungary).

Animal Identification
Animals were individually identified using numbers written on the tail with an indelible marker pen. The numbers were given on the basis of Citoxlab Hungary Ltd.' s Master File, for each animal allocated to the treatment groups. The cages were identified by cards, with information about study code, sex, dose group, cage number and individual animal numbers.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Remarks:

PEG 400

Details on oral exposure:

Formulation
The test item was freshly formulated at a concentration of 200 mg/mL in the vehicle, in the Pharmacy of Citoxlab Hungary Ltd. on the day of administration. The formulation container was stirred continuously up to finishing the treatment.

Vehicle Selection
The selection of the vehicle was made during trial formulations with the test item. The final choice of vehicle was approved by the Sponsor.
On the basis of the trial formulations with the test item, the vehicle used was PEG 400.
Vehicle: PEG 400 (Poly (ethylene glycol))
Batch number: BCBS1795V
Expiry date: 31 May 2018

Doses:

A limit of 2000 mg/kg bw dose was selected by the Sponsor in line with the guidelines.

No. of animals per sex per dose:

Initially, three females (assigned to Group 1) were treated at a dose level of 2000 mg/kg bw. As the test item did not cause mortality in this group a second group (Group 2) was treated at the same dose level.

Control animals:

no

Details on study design:

Procedure
A single oral gavage administration (dose administered at 10 mL/kg bw) was followed by a 14-day observation period. The day before treatment, food was removed at the end of the working day and the animals therefore fasted for a period of approximately 17 hours. Water was not withheld during this period. Animals were weighed before treatment. The test item was administered by oral gavage in the morning and food made available 3 hours after the treatment.

OBSERVATIONS
Clinical Observations
Clinical observations were performed at 30 minutes, 1, 2, 3, 4 and 6 hours after dosing and daily for 14 days thereafter. Individual observations were performed on the skin, fur, eyes, mucous membranes, respiratory, circulatory, autonomic and central nervous system, somatomotor activity and behaviour pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma.

Body Weight Measurement
The body weight was recorded the day before treatment (Day -1), on the day of the treatment (Day 0), Day 7 and Day 14.

NECROPSY
All animals were subjected to a necropsy and a macroscopic examination at the end of the study on Day 14. The animals were exsanguinated after verification of narcosis following an injection of pentobarbital sodium (Release; Lot No.: 106075, Expiry Date: July 2018, Produced by: Wirtschaftsgenossenschaft deutscher Tierärzte eG, Siemensstr. 14, 30827 Garbsen, Germany). After examination of the external appearance, the cranial, thoracic and abdominal cavities were opened and the appearance of the tissues and organs were observed. All gross macroscopic changes were recorded for each animal.

Statistics:

Not specified

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

BAL0001026 did not cause mortality at a dose level of 2000 mg/kg bw.

Clinical signs:

Treatment with BAL0001026 at the dose level of 2000 mg/kg bw did not cause any adverse clinical signs.

Body weight:

There were no treatment related effects on body weight or body weight gain during the observation period.

Gross pathology:

There was no evidence of treatment-related macroscopic changes at necropsy at a dose level of 2000 mg/kg bw.

Any other information on results incl. tables

INDIVIDUAL CLINICAL OBSERVATIONS

DOSE LEVEL: 2000 mg/kg bw, Treatment on Day 0                                                                SEX: FEMALE

Cage No.

Animal Number

Observations

Observation days

Frequency

0

1

2

3

4

5

6

7-14

30’

1h

2h

3h

4h

6h

1

636

Symptom Free

+

+

+

+

+

+

+

+

+

+

+

+

+

20/20

637

Symptom Free

+

+

+

+

+

+

+

+

+

+

+

+

+

20/20

638

Symptom Free

+

+

+

+

+

+

+

+

+

+

+

+

+

20/20

2

639

Symptom Free

+

+

+

+

+

+

+

+

+

+

+

+

+

20/20

640

Symptom Free

+

+

+

+

+

+

+

+

+

+

+

+

+

20/20

641

Symptom Free

+

+

+

+

+

+

+

+

+

+

+

+

+

20/20

Remarks:              + = present

                               h = hour‘ = minute

                               Frequency of observations = number of occurrence of observations / total number of observations

 

INDIVIDUAL BODY WEIGHT AND BODY WEIGHT GAIN

DOSE LEVEL: 2000 mg/kg bw, Treatment on Day 0                 SEX: FEMALE

Cage No.	Animal Number	Body weight (g) Days				Body Weight Gain (g)
		-1	0	7	14	-1-0	0-7	7-14	-1-14
1	636	256	238	259	270	-18	21	11	14
	637	237	225	256	269	-12	31	13	32
	638	241	227	265	280	-14	38	15	39
2	639	229	220	243	261	-6	23	18	32
	640	231	224	230	239	-7	6	9	8
	641	248	236	268	276	-12	32	8	28
Mean:		240.3	228.3	253.5	265.8	-12.0	25.2	12.3	25.5
Standard deviation:		10.3	7.1	14.4	14.7	3.8	11.3	3.8	11.9

 

INDIVIDUAL INTERNAL AND EXTERNAL MACROSCOPIC OBSERVATIONS

DOSE LEVEL: 2000 mg/kg bw, Treatment on Day 0                 SEX: FEMALE

Cage No.	Animal Number	Necropsy Date/ Necropsy Day	External Observations	Internal Observations	Organ/Tissue
1	636	12 September 2017 Day 14	No external observations recorded	No internal observation recorded	Not applicable
	637	12 September 2017 Day 14	No external observations recorded	No internal observation recorded	Not applicable
	638	12 September 2017 Day 14	No external observations recorded	No internal observation recorded	Not applicable
2	639	13 September 2017 Day 14	No external observations recorded	No internal observation recorded	Not applicable
	640	13 September 2017 Day 14	No external observations recorded	No internal observation recorded	Not applicable
	641	13 September 2017 Day 14	No external observations recorded	No internal observation recorded	Not applicable

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In the absence of any acute toxicity, BAL0001026 can be ranked as "Category 5" or "Unclassified" for acute oral toxicity according to the GHS criteria. Although this study was not designed to determine the acute oral LD50, under the conditions of this study, it is assumed for BAL0001026 to be above 2000 mg/kg bw in female CRL:(WI) rats.

Executive summary:

The single-dose oral toxicity of BAL0001026 was performed according to the acute toxic class method (OECD 423 and Commission Regulation (EC) No 440/2008 of 30 May 2008, B.1. tris) in CRL:(WI) rats.

 

Initially, three females (Group 1) were treated at a dose level of 2000 mg/kg bw. The test item was administered formulated in Poly (ethylene glycol) 400 (PEG 400) at a concentration of 200 mg/mL at a dosing volume of 10 mL/kg bw. A single oral treatment was carried out by gavage for each animal after food had been withdrawn overnight. Food was made available again 3 hours after the treatment. Clinical observations were performed at 30 minutes, 1, 2, 3, 4 and 6 hours after dosing and daily for 14 days thereafter. Body weight was measured on Days -1, 0 and 7 and Day 14. All animals were subjected to a necropsy and a macroscopic examination.

 

As no mortality was observed in group 1 a second group (Group 2) of 3 animals was treated at the same dose level using the methods described for Group 1.

 

Results

 

Mortality

BAL0001026 did not cause mortality at a dose level of 2000 mg/kg bw.

 

Clinical Observations

Treatment with BAL0001026 at the dose level of 2000 mg/kg bw did not cause any adverse clinical signs.

 

Body Weight and Body Weight Gain

There were no treatment related effects on body weight or body weight gain during the observation period.

 

Macroscopic Findings

There was no evidence of treatment-related macroscopic changes at necropsy in animals given 2000 mg/kg bw.

 

Conclusion:

In the absence of any acute toxicity, BAL0001026 can be ranked as "Category 5" or "Unclassified" for acute oral toxicity according to the GHS criteria. Although this study was not designed to determine the acute oral LD50, under the conditions of this study, it is assumed for BAL0001026 to be above 2000 mg/kg bw in female CRL:(WI) rats.